1. Field of the Invention
The invention relates to the field of digital data input/output units and more particularly to a credit card verifier unit for use in a credit card verification system.
2. Description of the Prior Art
The widespread use of credit cards has imposed upon the retail merchant the burden of determining whether the account represented by the number on a credit card is in good standing. The problem is an acute one for the merchant since he, rather than the company which issues the credit card, must stand the loss if he accepts a credit card for which the credit card company no longer will guarantee credit because of an overdue account, cancellation of the card, a report from the owner of the card that it has been lost or stolen, etc.
In large stores today, a clerk may use the telephone to check with a central office to determine the status of a credit card. However, with nationwide credit cards, such as oil company credit cards, the individual service station operator must rely upon long lists of invalid credit cards. These lists are sent to him periodically, such as weekly, by the credit card company. Because of the inconvenience and impracticability of referring to such long lists which also are not up-to-date, service station operators generally ignore them with the result that they accept invalid credit cards for sales, the amount of which is deducted by the credit card company from the payment made by the credit card company to the service station operator. Consequently, there is a great need for a simple low cost credit card verifier for the use of individual merchants, such as gasoline service station operators.